South Sudan's ruling Sudan People's Liberation Movement (SPLM) took another step toward reunification Tuesday as former political detainee Pagan Amum was reinstated as secretary general of the party.

The National Liberation Council (NLC), chaired by President Salva Kiir, announced after a four-hour meeting that it is revoking the decision it took last year to remove Amum from the key party post.

"What is left now are technical procedures for Pagan Amum to fully assume his office as the secretary general of the SPLM. This is good news for South Sudan, this is good news for SPLM members and the entire region and international community,” acting SPLM spokesman Akol Paul told reporters in Juba after the decision was announced.

The SPLM splintered into factions when South Sudan erupted in violence nearly 19 months ago.

“Today, we are united... This is one Sudan People’s Liberation Movement under comrade Salva Kiir Mayardit,” he said.

Former detainees

Amum and around a dozen other party officials were detained shortly after fighting broke in Juba on December 15, 2013. Mr. Kiir accused the group of party cadres of plotting to oust him in a coup. Most of the detainees were released to the custody of Kenyan President Uhuru Kenyatta after several weeks in detention. But Amum and three others were held for more than four months, during which time they appeared in court on treason charges.

Halfway through Amum's detention in February last year, a presidential decree read out on state television said Amum had been fired from the secretary-general position by Mr. Kiir.

The treason hearings began in March of last year. After a month of hearings, Justice Minister Paulino Wanawila ordered the high court to stay proceedings against Amum and the three other defendants. Wanawila said the government decided not to continue with the case against the four "for the purpose of promotion of dialogue, reconciliation, and harmony among the South Sudanese people."

Conditional welcome back

Reunification of the SPLM is not a done deal because the former vice president and SPLM in Opposition faction leader, Riek Machar, was not at the NLC meeting.

​Earlier this year, acting SPLM Secretary-General Anne Itto said all of the ousted party members, including Machar - who was deputy chairman of the SPLM until Mr. Kiir fired him last year - "will be welcome back... to resume their work as assigned to them.”

But, Itto said, there were conditions attached to the officials' reinstatement, namely that anyone who has been charged with a crime would have to go to court.

Like Amum, Machar was accused of treason for his alleged role in the events of December 2013 that triggered the fighting that still continues around the country. But unlike Amum, Machar has never been formally charged with treason. Machar had fled Juba when the violence broke out.